The present invention generally relates to systems that provide wireless data services to mobile terminals through both local-area wireless networks and wide-area cellular networks, and more particularly relates to techniques for improving the seamless handover of devices from one local area wireless network to another.
There is an emerging need for a convergence between fixed wireless data networks, such as those operated in a residential or office environment, and mobile wireless data networks, such as the Long-Term Evolution (LTE) and High-Speed Packet Access (HSPA) networks standardized by the 3rd-Generation Partnership Project (3GPP). This industry trend, and the emerging technologies and standards to facilitate this convergence, are broadly known as “Fixed Mobile Convergence” (FMC). One example of an industry effort in the FMC arena is the work undertaken by the Broadband Forum (BBF), which is defining interworking requirements between the 3GPP Evolved Packet Core (EPC) architecture and the IP-centric architecture of the BBF.
The residential wireless local-area network (WLAN) is one key to the success of FMC, because it is often the most commonly used fixed network access for ordinary users. Thus, one objective of FMC is to connect mobile phones and other mobile wireless devices (referred to as user equipment, or UE, in 3GPP terminology) to the EPC through the residential network. Connectivity between the residential network WLAN and a wide-area network (WAN) and hence to the EPC is enabled by the so-called “residential gateway” (RGW), a relatively inexpensive networking device. One challenge is to provide network-based IP mobility management for 3GPP UEs that are attached to the residential network.
A driving factor behind FMC is the growing user demand for data-intense applications, which puts high demands on wide-area wireless networks. Thus, wireless operators are seeking reliable technologies for “offloading” some of this demand from the wide-area wireless networks to alternative networks, including residential and office wireless local-area networks (WLANs). With this approach, user data takes an alternate path available in the overlay network, reducing burden on the 3G radio access network. However, seamless transitions, as the wireless data user moves between a WAN and a WLAN, and back again, are extremely important.
To date, efforts to develop technologies for supporting wireless data offloading have focused on this seamless switching between wide-area access technologies, such as 3GPP's HSPA and LTE radio access networks, and WLAN. However, additional efforts are needed to improve seamless transitions as mobile devices move from one WLAN to another in an FMC network. Solutions for supporting seamless transitions between WLANs should be deployable at a large scale, and should preferably be centralized, allowing service providers to have full visibility and control over large areas and over a very high number of users.